Automation machines, for example machine tools, processing machines, printing machines, handling machines, transport machines etc., are machines which have a modular structure and whose function and sequences are predefined by one or more control devices (so-called controllers, for example PLCs, MotionControl), the control devices controlling electrical energy consumers, such as actuators and sensors themselves, as well as the components driven by the actuators, such as motors, power supply units, drives, heating systems, cooling systems and many more. The control devices and sometimes also the energy consumers are connected via field bus networks, such as ProfiNet or SERCOS, as communication systems. They are therefore so-called field bus devices.
As part of the general trend for saving energy, efforts are also being made in automation machines to make operation as energy-saving as possible. One aspect in this case is the use of so-called energy modes (“EM”, also referred to as an energy-saving state). The energy consumption of automation machines having at least one energy consumer which consumes a different amount of energy in different operating modes can be optimized using energy management. Examples thereof are fans whose speed can be controlled and which are switched off in operating pauses, servo drives whose power supply is switched off during a standstill, or heating systems which are operated at a lower desired temperature value in operating pauses. For this purpose, one or more operating modes are assigned to different energy modes. In field bus devices, there are so-called energy profiles, that is to say agreements relating to specified data and their formats, for energy management. “Sercos Energy” or “PROFIEnergy” are mentioned here as examples. In this case, a plurality of additional intermediate modes are usually defined between the two limit modes “EM Power Off” (devices deenergized) and “EM Operational” (devices ready for operation). Energy modes are characterized by a large number of characteristic variables (also referred to as energy data here). These are, for example, the energy consumption in the respective mode, power consumption, time needed to transition between the modes, energy requirement during the transition process, minimum/maximum residence times in different energy modes.
In order to be able to achieve operation of the energy consumers which is as energy-saving as possible, the control device controlling the energy consumption must know the different energy modes or at least the energy data relating to the electrical energy consumers. If the energy consumers are directly supplied with energy by the control device, the control device can measure different electrical variables such as, in particular, maximum/minimum/average voltage, current, power, frequency etc. during operation as energy data and can use them to define energy modes. Energy consumers may also be connected to the control device via the field bus and can communicate the relevant data to the control device via said field bus.
Conversely, however, the control device cannot optimize the energy consumption of an energy consumer if it does not know the energy modes or energy data relating to the electrical energy consumers, for example because the data are not stored in the energy consumer or are stored in a form which cannot be used further (for example because a “simple” energy consumer itself does not have its own control unit or because the energy consumer is connected via a subordinate bus or sub-bus with different energy specifications), and the energy consumer is not supplied with energy via the control device and/or if the connection between the energy consumer and the control device is not suitable for transmitting the data. This is the case, in particular, with energy consumers connected to so-called I/O modules. Energy consumers are connected to I/O modules via analog (that is to say with a signal level which is variable over a range, for example 0 . . . 24 V) or digital (that is to say with (for example two) discrete signal levels, for example TTL) inputs and outputs and/or their own sub-buses, for example IO link, CAN bus or RS232/422/485.
It is therefore desirable to be able to optimize the energy consumption for such configurations as well.